AAON MODGAS-XWR2, Техническое руководство

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SEQUENCE OF OPERATIONS
MODGAS-XWR2 Technical Guide
20
Heating Mode
Heating Mode
Ignition Sequence for each Valve
Configuration
After Heat is enabled, the modulating valve(s) will move into the igni-
tion sequence. As long as there is a call for Heat, at least one stage will
be on. Despite the Supply Air Temperature relation to the Supply Air
Temperature Setpoint, the controller will continue heating as long as Heat
is enabled (through either binary enable or Modbus enable).
Here is what the ignition sequence looks like for each valve configuration:
1V1IGN1S : Valve 1 moves to the valve start position
(set in the hidden screen configuration and defaulted to 70%
modulation) and Heat 1 Relay is flipped on. The valve will
remain at this position until the proof of ignition time is satisfied.
In order to establish proof of ignition, the binary input used for
the proof of ignition must remain high for 20 seconds.
2V2IGN2S : Refer to 1V1IGN1S.
2V1IGN1S : Valve 1 & 2 move to the valve start position
(set in the hidden screen configuration and defaulted to 70%
modulation) and Heat 1 Relay is flipped on. Both valves are
connected to the same relay. The valve will remain at this
position until the proof of ignition time is satisfied. In order to
establish proof of ignition, the binary input used for the proof of
ignition must remain high for 20 seconds.
2V2IGN1S
: Valve 1 & 2 move to the valve start position
(set in the hidden screen configuration and defaulted to 70%
modulation) and Heat 1 & 2 Relay are flipped on. The valve will
remain at this position until the proof of ignition time is satisfied.
In order to establish proof of ignition, the binary input used for
the proof of ignition must remain high for 20 seconds.
Modulating Modes for each Valve
Configuration
After a configuration has completed its ignition sequence, then it moves
into a modulating mode. Here’s what the modulating modes look like
for each valve configuration:
1V1IGN1S : The PID loop runs every 10 seconds and
determines the modulation percentage for the one variable
valve. Then, the valve moves to the correct position. During the
modulation sequence, if the valve position is below 55%, the low
speed fan relay will energize as long as it remains below 55%.
Once it goes above 55%, the relay will de-energize and move the
fan back into high speed.
2V2IGN2S : The PID loop runs every 10 seconds and
determines the modulation percentage for the one variable valve.
Then, the valve moves to the correct position. Only after the
stage up delay requirement has been met will the board stage up
and open the second variable valve. After this, both valves will
move simultaneously to the same percent modulations. During
the modulation sequence, if the valve position is below 55%,
the low speed fan relay will energize as long as it remains below
55%. Once it goes above 55%, the relay will de-energize and
move the fan back into high speed.
2V1IGN1S : The PID loop runs every 10 seconds and
determines the modulation percentage for both variable valves.
Then, the valves move to the correct position. During the
modulation sequence, if the valve position is below 55%, the low
speed fan relay will energize as long as it remains below 55%.
Once it goes above 55%, the relay will de-energize and move the
fan back into high speed.
2V2IGN1S : Refer to 2V1IGN1S.
Additional Staging Information for each Valve
Configuration
During the heating sequence, if it is determined that there is currently not
enough/too many stages, then a stage up/down will occur, respectively.
For a stage up to occur, the valves that are currently in modulating
mode must be fully open (100% modulation) for the stage up time, and
the current supply air temperature must be at least two degrees below
the supply air setpoint. For a stage down to occur, the valves must be
closed as much as possible (35% modulation) and the current supply
air temperature must be at least 6 degrees above the supply air setpoint.
Additionally, all stages must stage down in the reverse order they staged
up (i.e. the first one to stage down is the last one to stage up). Below is
additional staging information for each of the configurations:
1V1IGN1S : The first stage up will turn on the fixed stage
attached to Heat 2 Relay. Stage three would be configured on
Heat 3 Relay and stage four on Heat 4 Relay. Additional stages
must be off board.
2V2IGN2S : Both on-board heat relays are used for
modulating valves, so the first stage up (i.e. turning on stage 2)
turns on the second modulating valve. Stage three would be
configured on Heat 3 Relay and stage four on Heat 4 Relay.
Additional stages must be off board.
2V1IGN1S : Refer to 1V1IGN1S.
2V2IGN1S : Both on-board heat relays are used for
modulating valves (stage 1), Stage two would be configured on
Heat 3 Relay and stage three on Heat 4 Relay. Additional stages
must be off board.